APS amphibious rifle
The APS Underwater Assault Rifle is an AK-47 derivative designed in the Soviet Union in the early 1970s as an underwater firearm. It was adopted in 1975, and manufactured by the Tula Arms Plant in Russia. Underwater, ordinary shaped bullets are inaccurate and very short range. The APS fires a steel bolt caliber 5.56mm (especially designed for this rifle and is often mistaken for 5.56x45mm) and 120mm long. Its magazine holds 26 cartridges. The APS's barrel is not rifled; the fired projectile is kept in line by hydrodynamic effects. As a result, the APS is somewhat inaccurate when fired out of water. The APS has a longer range and more penetrating power than spearguns. This is useful in such situations as shooting through reinforced dry suits, and protective helmets (whether air-holding or not), thick tough parts of breathing sets and their harnesses, and plastic casings and transparent covers of some small underwater vehicles. The APS is more powerful than a pistol, but is bulkier and takes longer to aim, particularly swinging its long barrel and big flat magazine sideways through water. History The rising threat of attacks by frogmen in naval bases caused various anti-frogman techniques to be developed, and in the USSR one of these was guard frogmen sent to stop the attackers. At first, the frogmen were armed only with knives and AK-type rifles. The AK-47 was carried in a waterproof case and could only be used on the surface, so the only effective underwater weapon against enemy frogmen was the knife. The SPP-1 underwater pistol was accepted in 1971, but soon proved to be useful only in close-up defence, not in attacking more distant targets. Vladimir Simonov undertook the job of developing an underwater assault rifle. To allow the rifle's mechanism to work underwater, there had to be room for the flow of the water pushed aside by moving parts and by the gas produced by the propellant explosive in the cartridge. The APS rifle was accepted for use in the mid-1970s. One special improvement was a perforated gas tube, and in the sighting. Its design engineer received a state award in 1983. As with the SPP-1, the first stage of the work was to develop a cartridge. A 5.45x39mm cartridge was lengthened by about 115 mm to fit the sharp-fronted steel bolt. Another cartridge version was designed that contained a miniature rocket, which when fired makes a visible streak in the water. Next, Simonov designed the rifle. The objective was ambitious; no one had ever before tried to build a functioning automatic underwater firearm. The most important problem was designing a receiver that could work underwater. Compared to air, water is relatively incompressible, so the structure had to let water move around easily; as a result, its receiver is open at the rear. Since it operates on the principle of gas discharge, it has a gas controller to let it work underwater and on land. The APS was adopted to develop in the mid-1970s, as Avtomat Podvodnyy Spetsnial'nyy APS. Afterwards, there was lenthy improvement work on the APS. One improvement was fitting a perforated gas pipe with a special shield to break up the emitted gas bubbles, making targeting easier and reducing the visibility of the bubbles, allowing stealthier firing of the weapon. The APS was the primary weapon of the Soviet frogmen. However, since the conception of this new weapon there were objections. It was the perfect weapon for the Soviet frogmen's underwater operations, but is was less use for Spetsnaz soldiers fighting on both land and under water. Therefore they mostly carried a SPP-1 for self-defense underwater and an AK-74 to fight on land. Category:Weapons Category:Weapons of Russia Category:Soviet Military Category:Soviet Army